1. Field of the Invention
The present invention is directed to glued screens for vibratory separator apparatuses and shale shakers; to methods for making such screens; to automated methods for making such screens; to screens made by such methods; to machines for making such screens, and to vibratory separator apparatuses and shale shakers with such screens.
2. Description of Related Art
The need for solids control in drilling mud used in hydrocarbon well drilling is well known in the prior art. Drilling mud, typically a mixture of clay and water and various additives, is pumped down through a hollow drill string (pipe, drill collar, bit, etc.) into a well being drilled and exits through holes in a drillbit. The mud picks up cuttings (rock) and other solids from the well and carries them upwardly away from the bit and out of the well in a space between the well walls and the drill string. At the top of the well, the solids-laden mud is discharged over a shale shaker, a device which typically has a series of screens arranged in tiered or flat disposition with respect to each other. The prior art discloses a wide variety of vibrating screens, devices which use them, shale shakers, and screens for shale shakers. The screens catch and remove solids from the mud as the mud passes through them. If drilled solids are not removed from the mud used during the drilling operation, recirculation of the drilled solids can create weight, viscosity, and gel problems in the mud, as well as increasing wear on mud pumps and other mechanical equipment used for drilling.
The present invention, in certain aspects discloses a screen assembly with layers glued together by, e.g., heated (then cured) moisture-curing hot melt glue, and methods for producing such glued screen assemblies.
The present invention, in certain aspects, provides a screen assembly made by an automated method according to the present invention. In certain embodiments of such methods moving mechanical apparatus powered e.g. by electricity or by fluid driven power apparatus (e.g. but not limited to, apparatus powered by fluid under pressure, e.g., but not limited to, hydraulic fluid under pressure powering hydraulic pumps and/or motors) applies glue in a desired pattern to one, two, three or more layers of screening material. Upon curing, the glue holds together screen assemblies according to the present invention which have one, two or more layers of screening material, bonded together or not, connected together or not, with or without a lower support structure, and with or without side hookstrip mounting apparatus. Any suitable screening material disclosed herein or disclosed in any patent or application referred to herein may be used. In one aspect screening material is used suitable for a screen assembly for screening drilling fluid introduced to a shale shaker that has one or more such screen assemblies. In certain aspects the glue used for applying a glue pattern is such that it rests on top of the screening material even in an uncured or un-set state and does not full through or out from the screening material and rests on it for further steps in the method, or is such that if it does tend to move downwardly through layer(s) of screening material its rate of movement is such that (and it is sufficiently viscous and/or it is sufficiently cured) it does not fall out from the screening assembly.
In certain methods that are automated according to the present invention, powered mechanical movement apparatus moves the layer(s) of screening material with respect to glue application apparatus. In one aspect the powered moving mechanical apparatus uses a patterned roller to apply glue in a pattern to screening material. In another aspect, one, two or a larger plurality of glue nozzles are moved above the screening material (which itself may be stationary or may be moving beneath the glue nozzles) to apply the glue in a desired pattern. In one particular aspect a plurality of spaced-apart glue dispensers on a manifold are moved above the screening material. In certain aspects the manifold is oscillated with respect to the screening material and, in one aspect, there are two, three or more such manifolds. Any desired glue pattern may be applied. A screen or screen assembly thus made according to the present invention may, optionally, be mounted to lower support, such as a tubular frame, on a strip support, rod support, on a layer of coarse mesh or gridwork, or on a perforated plate or perforated piece of sheet metal. Such mounting may be any suitable known method disclosed in the art and any suitable known frame, strip support, rod support, coarse layer, or perforated plate may be usedxe2x80x94including, but not limited to, those disclosed in any patent or application referred to herein. Alternatively, according to the present invention, hookstrips may be applied on spaced-apart sides of glued screening material(s).
In certain aspects of methods according to the present invention glue is applied with at least two nozzles so that lines of glue intersect and, at points of intersection, the glue pattern is stronger (due to the fact there is relatively more glue present at such points) than at points along either glue line where the lines do not intersect.
The present invention discloses, in at least certain aspects, a screen made by a method for making a screen for a vibratory separator, the method including placing a substrate or at least one layer of screening material below a glue application apparatus, the glue application apparatus including a main body and a plurality of movable glue nozzles movably connected to the body, and applying with the movable glue nozzles an amount of glue in a pattern to at least a portion of the substrate or to the at least one layer of screening material by moving the movable glue nozzles over the substrate or over the at least one layer of screening material. In one such method in which a glue pattern is applied to a substrate, the glue pattern while still manipulable is removed from the substrate and is then applied in pattern form to screening material.
The present invention discloses, in certain embodiments, a screen for vibrating screen apparatus. The screen has one or more upper layers of screen, screen cloth, and/or mesh. The layer or layers may be mounted on frame apparatus which may include a solid side support on each of two spaced apart sides of the layer(s), or a full four sided screen frame, with or without one or more interior crossmembers such as tubular rods or hollow tubular members extending between the sides. A strip support or strips of support material (e.g. flat steel) may be used beneath screen layer(s). In some aspects, hookstrips are used on opposed sides or ends of a screen made by a method according to the present invention so that it can be mounted in a shaker or other separator apparatus. Any known hookstrip configuration may be used according to the present invention.
The present invention, in one embodiment includes a shale shaker with a frame; a xe2x80x9cbasketxe2x80x9d or screen mounting apparatus; one or more screens according to the present invention as described above and below; and basket vibrating apparatus.
The present invention discloses, in certain aspects, a screen made by methods for making screens and screen assemblies as disclosed herein for a vibratory separator, the methods including placing at least two layers (in some cases two, three or four layers) of screening material adjacent one another one on top of the other, introducing an amount of glue to the at least two layers of screening material for adhering at least portions of them together, the amount of glue introduced to the at least two layers of screening material from one, two or more manifolds each with a plurality of glue dispensing nozzles or tubes above screen layer(s) moved beneath the manifolds.
It is, therefore, an object of at least certain preferred embodiments of the present invention to provide:
New, useful, unique, efficient, non-obvious screens made by methods for making screens and screen assemblies; screen assemblies with multiple layers of screening material; screen assemblies with one or more lower coarse screen members and one or more upper fine screen members; such screens with a lower support beneath the screen layers and, in one aspect, with one or more bottom strip members, support strips or rods; such screen assemblies with a lower support frame or a lower support perforated plate; such screen assemblies in which screening material of adjacent screen layers is glued together with glue, e.g. but not limited to, moisture-curing hot melt glue; and shale shakers or vibratory separators with any such screen assemblies;
Such screens made by an automated method with powered moving mechanical apparatus for applying heated glue in a pattern to one or more layers of screening material and, in one aspect, with powered mechanical apparatus for moving the screen layer(s) beneath the glue apparatus;
Such screens or screen assemblies made with a gluing system that has one, two or more manifolds each with a plurality of spaced-apart glue dispensers for applying a pattern of glue to screen layer(s) moving beneath the manifolds; and, in one aspect, with hot-melt glue sufficiently viscous to stay on a layer or layers of screening material to cure and glue the layers together;
A shale shaker or vibratory separator with one or more such screens or screen assemblies; and
Methods of making such screens and machines for making them.
The present invention recognizes and addresses the previously-mentioned problems and long-felt needs and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one of skill in this art who has the benefits of this invention""s realizations, teachings, disclosures, and suggestions, other purposes and advantages will be appreciated from the following description of preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent""s object to claim this invention no matter how others may later disguise it by variations in form or additions of further improvements.